From corporate events to Michelin-starred restaurants, the Bay Area consumes vast quantities of prepared food every day, contributing to the estimated 30 to 40 percent of food that gets wasted in the United States.

And yet an estimated 4.9 million Californians lack consistent access to adequate meals, according to the California Association of Food Banks, and one in four Silicon Valley residents are at risk of hunger, according to Second Harvest Food Bank. That's why local restaurants and catering companies have partnered with nonprofit Peninsula Food Runners to donate leftovers rather than tossing them in the trash.

Founded in 2013 by Maria Yap, the organization matches donors, volunteers and recipients, delivering an average of 35,000 meals weekly across the Midpeninsula. Peninsula Food Runners delivers food to around 200 organizations that then distribute it to low-income housing residents, senior centers, families and the homeless, among other communities -- for a total of 8,000 individuals served.

"Basically the premise is that you have so much food here, all this surplus," Yap said. "So why not give it to people in need?"

Yap, who lives in San Francisco, said she grew up in Malaysia watching her social worker mother make case calls, an experience that made her acutely aware of food insecurity.

"Many of her clients were victims of unfortunate circumstances, such as fires, monsoon flooding, homelessness, drug abuse, domestic violence, child abuse, etc," Yap said on the Food Runners website. "Food was always connected somehow."

In the 2000s, while training as a chef in San Francisco, Yap started volunteering at Food Runners San Francisco. The organization had developed a system in which volunteers picked up food from restaurants to remove logistical barriers to donation. But the Midpeninsula had no such system, so Yap decided to replicate the San Francisco model. Now, Peninsula Food Runners serves both San Mateo and Santa Clara counties. About 11 percent of Santa Clara County residents and 17 percent of San Mateo County have food insecurity, according to the nonprofit.

Peninsula Food Runners aims to take the onus off businesses by researching recipients and transporting food, which ranges from fresh produce to gourmet steak meals. The organization relies on a customized software system called ChowMatch, which Yap's husband Tod created in 2011. The app asks that donors sign up once and then matches them with volunteers and recipients on a case-by-case basis.

On ChowMatch, recipient organizations can specify their clients' needs to ensure they get the right kind of food at the right time. Some families have kitchens where they can prepare fresh produce, for example, while others don't and require prepared meals. Because the system addresses recipients' unique living situations, Yap said, nobody is forced to throw away food they cannot use.

The 500 Food Runners volunteers -- a number Yap said is growing "tremendously" -- pick up the donated food and deliver it. Aspiring volunteers have to pass a food safety test in order to participate.

Local restaurants have caught on. Zume Pizza, the Mountain View pizza delivery company known for its semi-automated production, partners with the organization to donate between seven and 25 pizzas daily.

"I personally think that food waste is one of the stupidest problems in the entire world," said Zume co-founder Julia Collins. "There should be no reason why we make food and throw it in the trash ... It makes a lot of sense to donate your fresh food to a partner who can give it to somebody who's hungry."

Still, the barriers to donation remain high for many food producers.

Richard Vo, Palo Alto team leader for catering company EAT Club, said that many restaurants and caterers err on the side of having too much food rather than too little. Although many businesses give excess food to their employees at the end of the day, they are still overwhelmed with leftovers, particularly for caterers that produce it in large quantities.

Even Zume's "micro-forecasts" for daily business, which rely on artificial intelligence, aren't always perfect.

Liability concerns present another barrier to addressing food waste. Many cities have laws against sharing food with people on the street, making restaurant owners wary of accidentally breaking the law. And last summer in San Jose, city officials cracked down on food giveaways in a local park.

With this in mind, Vo said, coming up with effective ways to handle waste is an "extra process" that restaurant owners are often hesitant to take on in addition to the daily stresses of running a business.

Local tech companies make up the bulk of donations, though Yap said that recently more restaurants have expressed interest in donating. LinkedIn, for example, donates excess catered meals every day (and has also supported Peninsula Food Runners financially). Other prolific givers include Salesforce and Sequoia Capital.

And while EAT Club donates between 20 and 100 meals every day, several of their client companies also donate excess food, creating a secondary round of donations between caterers and tech firms.

For the many people who have to choose between eating and other necessities, like paying for medication or electricity, Peninsula Food Runners fills a critical need.

"What we offer is a supplemental meal that they don't have to worry about," Yap said.

For more information about Peninsula Food Runners, go to peninsulafoodrunners.org.